Method of orienting electrically conductive bodies, preferably non-magnetic ones, in a magnetic field and apparatus for performing same

ABSTRACT

A method of orienting electrically conductive bodies, preferably, non-magnetic ones, in a magnetic field, wherein a body is oriented under the action thereupon of a non-uniform magnetic field induced by an alternating electric current, by means of electromagnets connected to an alternating current supply, the pole pieces of these magnets defining therebetween an orientation zone, whereby a body can be oriented both from an arbitrary position and from any intermediate position into a predetermined final spatial position, with the final oriented position of the body being retained.

United States Patent [1 1 Ioffe et al.

[ 1 Dec. 30, 1975 METHOD OF ORIENTING ELECTRICALLY CONDUCTIVE BODIES,PREFERABLY NON-MAGNETIC ONES, IN A MAGNETIC FIELD AND APPARATUS FORPERFORMING SAME [75] Inventors: Benyamin Alexandrovich Ioffe;

Robert Karlovich Kalnin; Vyacheslav Semenovich Dorcfeev; ViktorGeorgievich Sirotenko, all of Riga; Vladimir Borisovich Larin, Smolensk;Gunar Yanovich Sermons; Alexandr Alexandrovich Shevchenko, both of Riga,all of U.S.S.R.

Institut Fiziki Akademii Nauk Latviiskoi SSR, U.S.S.R.

221 Filed: Jan. 16,1974

2| Appl. No.: 433,885

Related US. Application Data [63] Continuation of Ser. No. 885,190, Dec.15, 1969.

[73] Assignee:

[30] Foreign Application Priority Data Dec. 25, 1968 U.S.S.R 1289054Dec. 25, 1968 U.S.S.R 1289056 52 U.S.Cl. ..33s/2s4;33s/250;335/2s1;335/282; 335/299 51 lnt.Cl. ..H01F 7/20 [58] Field of Search 335/229,234, 250, 281,

[56] References Cited UNITED STATES PATENTS 698,024 4/1902 Knapp 335/2342,400,869 5/1946 Lovell 335/250 V 3,054,026 9/1962 Lovell 335/250FOREIGN PATENTS OR APPLlCATlONS 181,481 10/1964 U.S.S.R 335/229 PrimaryExaminerJ. D. Miller Assistant ExaminerFred E. Bell Attorney, Agent, orFirmHaseltine, Lake & Waters [57] ABSTRACT A method of orientingelectrically conductive bodies, preferably, non-magnetic ones, in amagnetic field, wherein a body is oriented under the action thereupon ofa non-uniform magnetic field induced by an alternating electric current,by means of electromagnets connected to an alternating current supply,the pole pieces of these magnets defining therebetween an orientationzone, whereby a body can be oriented both from an arbitrary position andfrom any intermediate position into a predetermined final spatialposition, with the final oriented position of the body being retained.

1 Claim, 9 Drawing Figures U. S Patent Dec 30, 1975 Sheet 1 0f 53,930,212

US. Patent Dec.301975 Sheet2of5 3,930,212

US. Patent Dec.30, 1975 Sheet3of5 3,930,212

US. Patent Dec. 30, 1975 Sheet40f5 3,930,212

U.S. Patent Dec.30, 1975 shws 0f5 3,930,212

METHOD OF ORIENTING ELECTRICALLY CONDUCTIVE BODIES, PREFERABLYNON-MAGNETIC ONES, IN A MAGNETIC FIELD AND APPARATUS FOR PERFORMING SAMEThis case is a continuation of application 885,190, filed Dec. 15, 1969.

The present invention relates to a method of orienting electricallyconductive bodies, including, non-magnetic ones, in a magnetic field andto and is useful in various industries in which electrically conductivebodies are to be oriented for further treatment. The invention can bewidely used for introducing automation into processes which variousarticles and workpieces are to be oriented in the course of their beingmanufactured or assembled into units, machines, apparatus, and so forthA method of orienting electrically conductive bodies is known, accordingto which the orientation operation is performed due to an interaction ofthe magnetic field of a permanent magnet with alternating electriccurrents induced in the bodies being oriented.

This known method, however, provides merely for orienting successivebodies or workpieces from an arbitrary position into a singlepredetermined intermediate position, and does not provide for orientinga body into a desired final position both from an arbitrary position andfrom any intermediate position, depending on a characteristic feature ofsaid body, e.g., a projection, an aperture, a groove or slit in one ofthe sides of the body, a structural difference between the portions ofthe body, and so forth. Additionally this known method is incapable ofretaining the bodies being oriented in a desired position, which isessential for the majority of production processes.

It is an object of the present invention to overcome the disadvantagesof the known method.

The present invention has as a more specific object the provision of amethod of orienting electrically conductive bodies, includingnon-magnetic ones, in a magnetic field, and of apparatus for performingthe same which method should provide for a bodys being simultaneouslyoriented and retained in an oriented position, relative to two or moreperpendicular reference planes, This method should further provide forsimple and efficient control of the parameters of the magnetic fieldcreated in the zone where said bodies are oriented, and shouldadditionally provide for either simultaneous orientation of severalstreams of successive bodies, or for orienting successively suppliedbodies under the action of different types of non-uniformity of amagnetic field, as these bodies are falling through a plurality ofserially arranged magnetic systems.

According to the present invention, a method is provided for orientingelectrically conductive bodies wherein a body is oriented under theaction of a nonuniform magnetic field induced by an alternating electriccurrent, a inductance of said field decreasing in a direction toward thecentral portion of the orientation zone.

It is advantageous for the frequency of said alternating electriccurrent inducing said magnetic field to be selected in accordance with apredetermined ratio of the inductive reactance to the resistance of saidbody being oriented.

A method, embodying the present invention, may be performed by thefollowing types of apparatus:

an apparatus comprising at least one electromagnet having a windingadapted to be connected to an alternating current supply source and amagnetic core including at least one pair of pole pieces definingtherebetween an orientation zone, said pole pieces beinig shaped andarranged relative to each other to create a non-uniform magnetic fieldof which the inductance decreases toward the central portion of saidorientation zone; each one of said pole pieces preferably having atleast one V-shaped cut facing said orientation zone;

an apparatus comprising at least two electromagnets, each including aC-shaped magnetic core, said respective magnetic cores being adjustablymounted for selective positioning thereof relative to one another, eachone of said electromagnets being adapted to be connected to a source ofalternating electric current of adjustable frequency;

an apparatus comprising an electromagnet including a plurality ofgenerally C-shaped magnetic cores, all of said magnetic cores beingassociated with a pair of pole pieces the first one of said pair of polepieces being disposed above the second one of said pair of pole pieces,said first pole piece having at least one passage therethrough throughwhich a body can be introduced into an orientation zone, said secondpole piece having at least one aperture therethrough through which abody can leave said orientation zone after the orientation operation.

In a further modification of the last-mentioned type of apparatus, themagnetic core assembly may be a multi-level one, having a respectivepole piece at each of the levels thereof, all of said apertured polepieces being preferably shaped as truncated pyramids, the small bases ofsaid truncated pyramids of the adjacent ones of said pole pieces facingeach other, the crosssectional shape of each one of said aperturesthrough which a body can leave said orientation zone corresponding tothe contour of said body in a plan view.

The herein disclosed method of orienting electrically conductive bodiesin a magnetic field and the apparatus performing same have been found toattain successfully the above specified aims and objects.

The present invention will be better understood from the followingdetailed description of some of the preferred embodiments of a method oforienting electrically conductive bodies in a magnetic field, as well asof several embodiments of apparatus for performing the same, with duereference being had to the accompanying drawings, wherein:

FIG. 1 shows schematically and in perspective a general view of anapparatus, embodying the invention, with pole pieces having a V-shapedcutaway portion;

FIG. 2 illustrates the distribution of magnetic flux in the spacebetween the pole pieces and indicates the forces acting upon a body inthe respective areas of the orientation zone;

FIG. 3 shows in detail the pole pieces of an apparatus, according toFIG. 1, having their respective V- shaped cuts slanting relative to avertical plane, defining an orientation zone which flares up wardly;

FIG. 4 shows in detail the pole pieces of an apparatus, as shown in FIG.1, each of the pole pieces having a pair of adjacent V-shaped cuts;

FIG. 5 shows an apparatus, embodying the invention, having a pair ofelectromagnets, each with a Cshaped magnetic core;

FIG. 6 shows a structure wherein a plurality of apparatus of the kindshown in FIG. are mounted for relative adjustable positioning;

FIG. 7 shows the general view of an apparatus, embodying the invention,including an electromagnet with a plurality of individual C-shapedmagnetic cores associated with a single pair of pole pieces, adapted fororienting a single stream of successive bodies;

FIG. 8 shows a view similar to that in FIG. 7, with pole pieces adaptedfor orienting simultaneously two parallel streams of successively fedbodies; and

FIG. 9 shows an apparatus, of the kind shown in FIG. 7, having amulti-level magnetic core, with a pole piece at each level.

Referring now in particular to the appended drawings, the hereindisclosed method of orienting electrically conductive bodies resides inthe following:

A body 1 (FIG. 1) is introduced into the space between the pole pieces,where a non-uniform magnetic field created by an alternating electriccurrent acts thereupon, whereby the body 1 is oriented in a desireddirection. In the herein dislosed example, the nonuniform electric fieldis created by an electromagnet having a winding 2 connected to analternating-current supply, and a magnetic core 3 with a pair of polepieces 4 and 5, defining therebetween an orientation zone for thebody 1. It is essential that this non-uniform magnetic field created bythe alternating current should have its inductance decreasing toward thecentral portion of the orientation zone, which can be attained byshaping the pole pieces correspondingly, and also by appropriatelypositioning them relative to each other. In the apparatus illustrated inFIG. 1 this feature is attained by the pole pieces 4 and 5 beingprovided each with a V-shaped cutaway portion, or cut facing theorientation zone. Such configuration of the pole pieces is responsiblefor the creation of a distinct retaining plane (i.e., a plane where abody is retained in an oriented position thereof), which plane, as canbe seen in FIG. 2, is disposed in the central portion of the spacebetween the pole pieces, intermediate the spaced apices of the V-shapedcuts. The inductance in this portion of the orientation zone is lowerthan in any other portion thereof. The herein disclosed method providesfor adjusting the torque acting upon the body being oriented, by meansof controlling correspondingly in any known way the frequency of thealternating current creating the magnetic field. It is possible, forexample, to select a frequency so that the inductive reactance and theresistance of the body equal each other, in which case the torque actingupon the body acquires a maximal value.

The V-shaped cuts in the pole pieces 4 and 5 can be made slantingrelative to a vertical plane, as is shown in FIG. 3, in which case anupwardly flaring orientation zone is defined, whereby a body is finallyretained in an oriented position at a given point. The body 6 shown byway of example in FIG. 3 is a yoke, which in the orientation zone of thekind herein illustrated would be oriented from any initial position intothe finally oriented position shown, and this oriented position would beretained.

The angular value of the V-shaped cut and the degree of the slantingthereof relative to a vertical plane are selected in order to obtain adistinct retaining plane, in accordance with the actual spacing of thepole pieces.

The pole pieces may have two or even more V- shaped cuts each, as isshown in FIG. 4. In this manner it becomes possible to retain a body inan oriented position, depending on several characteristic featuresthereof simultaneously, e.g., by several features. Shown by way ofexample in FIG. 4 is a cylinder-shaped body having a dielectric housing7 receiving thereinside an electrically conductive non-magnetic memberincluding a thin rod 8 carrying two discs 9 and 10. Bodies of this kindcan be oriented by the herein disclosed method and can be retained in anoriented position, depending on the position of their internal members.To this end, the distance between the apices of the two V-shaped cuts ofeach of the two pole pieces is made equal to the spacing between thediscs 9 and 10 of the internal member of the body. Moreover, anorientation zone of the last mentioned shape can be used for orientingand retaining more than two streams of successive bodies simultaneously,provided the dimensions of the bodies correspond to the spacing betweenthe respective pairs of V-shaped cuts facing each other, and that thebodies are oriented depending on a single characteristic featurethereof.

The herein disclosed method of orienting electrically conductive bodiescan be performed by another, basically similar apparatus, wherein anon-uniform magnetic field acting upon the bodies being oriented iscreated by two electromagnets including their respective C-shapedmagnetic cores l1 and 11 (FIG. 5) and windings l3 and 14 adapted to besupplied with an alternating electric current. The two electromagnetsare so positioned that their similar pole-pieces are brought adjacent toeach other and create a common magnetic field in the orientation zone.In the example illustrated in FIG. 5 the body being oriented is anasymmetrical stem 15 heaving a threaded end, whereby the two endportions of the stem 15 feature different electrical conductivity, and,therefore, are oriented in the magnetic field with the desired one ofthe two ends leading.

A structure including two electromagnets is particularly suitable forestablishing a desired degree of the non-uniformity of the magneticfield in the orientation zone, which is attained by placing the lowerpair of the pole pieces of the two electromagnets at a distance fromeach other, which is slightly greater than the respective dimension ofthe body to be oriented, while the other, upper pair of the electrodesis spaced from each other by a distance which is experimentally found tobe the most suitable for accurate orientation. Owing to interaction ofsuch fanshaped non-uniform magnetic field with the body being oriented,there are applied to the opposite end portions of the body the twounequal resultant components of the electrodynamic forces, F, and Frespectively, which tend to oust the body from the orientation zone,whereby the inequality of these components produce a torque which turnsthe body into a position indicated by dotted lines in FIG. 5. By turningthe two electromagnets relative to each other in a given plane andspacing them suitably in the same plane, it is easy to form anon-uniform magnetic field in this very plane of the orientation zone,whereas for forming an orientation zone featuring a three-dimensionallynon-uniform magnetic field, it is advisable to employ more than twoC-shaped electromagnets.

Illustrated in FIG. 6 is yet another apparatus, embodying the invention,which comprises four electromagnets with their respective magnetic coresl6, 17, 18, 19 and windings 20, 21, 22, 23 which latter are eitherconnected to a single source of single-phase alternating current, orelse are connected to their respective individual sources, and thuscreate the respective magnetic fields characterized by differentfrequencies. The respective adjustable clamps 24, 25, 26, 27 carried bythe upright supports 28, 29, 30, 31 hold the four electromagnets abovethe base 32, so that the positions of the electromagnets above the base32, so that the positions of the electromagnets can be selectivelyadjusted relative to one another. With the electromagnets thus arranged,successive bodies in the shape of, for example, square cups may be notonly oriented for their butt ends to acquire a desired position, butthey may be simultaneously rotated into a desired position of their sidewalls.

A method of orienting successive bodies, embodying the presentinvention, can also be performed by an apparatus illustrated in FIG. 7.As can be seen from FIG. 7, the electromagnet in the last mentionedapparatus comprises a core assembly including a plurality of individualC-shaped core members 35 associated with a single pair of pole pieces 33and 34. The pole piece 33 is positioned above the pole piece 35, andeach of the plurality of cores 35 has wound thereabout a respectivewinding 36 having a limited number of coils. The upper pole piece 33 hasa vertical passage therethrough for a body 37 to be introduced into theorientation zone, whereas the lower pole piece 34 has its own verticalpassage, through which the body can leave the orientation zone after theorientation operation, the cross-sectional shape of the passage in thelower pole piece corresponding to the contour of the body in a planview, in a desired oriented position of this body. The pole pieces 33and 34 are shaped as truncated pyramids, the lower bases of the twopyramids facing each other, whereby the magnetic flux is concentratedwithin the peripheral outline of the body 37 in any initial positionthereof. With the magnetic core thus arranged, there is a funnel-shapednon-uniform mangetic field created in the orientation zone, which fieldprovides for orienting successive bodies even in the course of theirshort-distance descent through the orientation zone. By the cores 35being arranged about the whole periphery of the pole pieces 33 and 34,it becomes possible to attain a magnetic field which is more evenlydistributed in the orientation zone, the inductance of the fielddecreasing toward the central portion of the zone.

The magnetic core structure of the kind shown in FIG. 7 can be readilybuilt up from a desired number of easily attachable core members 35. Byhaving in stock a comparatively small set of such core members, itbecomes possible to build up various apparatus of a similar kind withextreme ease and flexibility.

An apparatus of the last-mentioned kind can be used also for orientingsimultaneously several streams of succesively fed asymmetrical bodies.For example, for orienting simultaneously two streams of bodies 38 and39, respectively (FIG. 8), the apparatus features two orientation zones,each of them being similar to the orientation zone illustrated in FIG.7.

Moreover, an apparatus of the last-mentioned kind may be a multi-levelone, which arrangement shows utmost efficiency, when a body cannot beoriented into a final desired position within a single space between apair of pole pieces.

Illustrated in FIG. 9 is an apparatus with a two-level magnetic corestructure, which apparatus is meant for orienting, for example,cross-shaped pieces 40. The first stage, or level of this apparatusreliably orients the body 40 by one of the planes thereof relative tothe direction of its descent through the apparatus, whereas in thesecond stage, or level of the apparatus, i.e., in the orientation zonedefined between the pole pieces 33' and 34, the body is rotated into adesired spatial position of its cross-shaped cross-section about theaxis of its descent.

All of the above described kinds of apparatus can be easily associatedwith known feeding arrangements and can be trusted for high efficiencyand speed of their operation.

What is claimed is:

1. A method of orienting and fixing nonmagnetic electrically conductivebodies under the action of a non-uniform magnetic field induced by analternating electric current, said method comprising distributing, in azone of simultaneous orientation and fixation, the inductance of themagnetic field in such a way that bodies are acted upon by a field withat least one nonuniform part, forming a central plane section in saidpart of the field, the inductance of which field tapers in said sectiontowards a center of fixation corresponding to a minimum value of theinductance of the field, and forming the cross-section of said sectionrelative to the field direction depending upon the form of thecrosssection of the body in its position of fixation.

1. A method of orienting and fixing nonmagnetic electrically conductivebodies under the action of a non-uniform magnetic field induced by analternating electric current, said method comprising distributing, in azone of simultaneous orientation and fixation, the inductance of themagnetic field in such a way that bodies are acted upon by a field withat least one nonuniform part, forming a central plane section in saidpart of the field, the inductance of which field tapers in said sectiontowards a center of fixation corresponding to a miNimum value of theinductance of the field, and forming the cross-section of said sectionrelative to the field direction depending upon the form of thecross-section of the body in its position of fixation.